This conjecture is false, A and C don't have to be complementary angles.
Let Angle A be 100 and Angle B be 80 degrees. They are supplementary (sum of 180).
Let Angle C be 100 and Angle B is still 80 degrees. They are supplementary.
However, Angle A and Angle C are not complementary (sum of 90).
Answer
Let t be number of minutes since tap is opened
water is increased by 20 gallons of water per minute.
sugar increase rate of 3 pounds per minute
water :- W(t) = 350 + 10 t
sugar :- S(t) = 10 + 3 t
concentration
C(t) = 
at t = 15 minutes
C(15) = 
C(15) = 
C(15) = 0.11
at beginning t = 0 minutes
C(0) = 
C(0) = 
C(0) = 0.0286
C(15) > C(0)
hence, concentration is increasing as time is passing.
Answer:
x=75
Step-by-step explanation:
Answer:
x = 3.2
Step-by-step explanation:
Since, intercepts made by parallel lines on the transversals are in proportion.
AB = BC.... (given)
From equations (1) & (2)
Therefore,
7x - 9 = 2x + 7
7x - 2x = 9 + 7
5x = 16
x = 16/5
x = 3.2